Inventio, dispositio, elocutio: three lenses for analysing argumentation in geometry textbooks

Abstract

Starting from the corpus of the project Italmatica. Comprendere la matematica a scuola, fra lingua comune e linguaggio specialistico of the Swiss National Science Foundation, an analysis of examples from Italian-language geometry textbooks of primary and secondary schools is presented. The analysis is based on the application of classical rhetorical categories: inventio, dispositio and elocutio, which are nowadays related to the domains of linguistic studies, in particular theories of argumentation. Through the analysis, we highlight on one hand the depth of the reflections that these theoretical lenses allow us to reach in dissecting an argumentative text in mathematics, on the other hand, we show the great variety of possible choices adopted by textbooks, which can have a communicative effect on the reader-student.